Messages in this thread | | | Date | Mon, 28 Mar 2022 16:58:52 +0200 | Subject | Re: [PATCH 1/3] dt-bindings: mmc: mmci: add a property to disable DMA LLI | From | Yann Gautier <> |
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On 3/25/22 21:12, Linus Walleij wrote: > On Tue, Mar 15, 2022 at 9:26 AM Yann Gautier <yann.gautier@foss.st.com> wrote: > >> The STM32 variant uses an internal DMA, and the DMA functions are in its >> dedicated file. So I was planning to do the same as what is done in >> meson-gx-mmc.c: using a bounce buffer to copy from/to in case DMA >> constraints are not fulfilled. Not sure it can help for Ux500. >> >> Ulf, before I send my new series (although it is not ready yet), would >> you be OK with the bounce buffer idea? > Hi Linus,
> Would it not be better if the bounce buffer is something available > for all MMCI variants and not restricted to the STM32 DMA add-on?
The issue was seen with the internal DMA of the STM32 variant of PL180.
> > What I'm thinking is that this is a problem with the MMCI hardware > rather than with the DMA hardware, so the problem kind of gets > fixed in the wrong place if the bounce buffer is in the DMA add-on > code. > > Maybe this is how you fixed it in later patches, I'll take a look.
I've pushed a new version there to correct latest remarks from Ulf: https://lore.kernel.org/all/20220328145114.334577-1-yann.gautier@foss.st.com/
> > Yours, > Linus Walleij
Best regards, Yann
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